Crossword-Solution: SLAGS 5 letters, 30 clues 🏆 scrabble score: 6

The greater number consisted merely of a ring of red scoriae or slags, cemented together: and their height above the plain of lava was not more than from fifty to a hundred feet; none had been very lately active.

Lavas present a general resemblance to the slags and clinkers which are formed in our furnaces and brick-kilns, and consist, like them, of various stony substances which have been more or less perfectly fused.

The greater number consisted merely of a ring of red scoriæ or slags cemented together: and their height above the plain of lava was not more than from fifty to a hundred feet: none had been very lately active.

Some of these pass up the chimney in a gaseous state, whilst others remain in the form of melted slags, floating on the surface of the iron, which is fused by the heat thus set at liberty.

The plan, therefore, of heating the air before driving it into the furnace saves, obviously, the whole of that heat which the fuel must have supplied in raising it from the temperature of the external air up to that of 600 degrees Fahrenheit; thus rendering the fire more intense, and the glassy slags more fusible, and perhaps also more effectually decomposing the iron ore.